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Ultra-high performance concrete (UHPC) is becoming a prevailing construction material in protective engineering. However, an insufficient research basis causes difficulty in the anti-explosion structural design of UHPC. To investigate the blast resistance of the UHPC slab (UHPCS), contact explosion tests were carried out. UHPCS exhibited superior blast resistance and a lower threshold range of failure modes than the normal reinforced concrete slab (NRCS). Compared with the NRCS, the UHPCS reached a lower damage level under the same scaled distance and had smaller craters and spalls, fewer cracks, and an absence of cross-shaped cracks. For NRCS, failure modes of medium spall, severe spall, and perforation were reached under charges of 1.0, 1.6, and 2.2 kg. In contrast, UHPCS reached medium spall, severe spall, and perforation under charges of 1.6, 3.3, and 5.0 kg. The scaled slab thicknesses (T/W1/3) of the medium spall, severe spall, and perforation of the NRCSs were 1.17, 1.27, and 1.32 times larger than those of the UHPCSs, respectively. The formulae for predicting the spall and perforation thresholds of the UHPCSs were proposed. The reduction factors were used to evaluate the mitigation effect of the blast damage on the UHPC compared to that on the NRC. The reduction factors of the crater diameter () and the spall diameter () were determined to be 0.507 and 0.721, respectively. For quantitative analysis of the anti-explosion performance of UHPC, a simple estimation method for predicting the dimensions of the crater and spall of the UHPCS was proposed and verified based on the dimensional analysis method. [ABSTRACT FROM AUTHOR]

Epigallocatechin-3-gallate (EGCG), a main active catechin in green tea, was reported to attenuate renal injury and hypertension. However, its effects on salt-induced hypertension and renal injury remain unclear. In the present study, we explored its effects on hypertension and renal damage in Dahl rats with salt-sensitive hypertension. We found that EGCG could lower blood pressure after 6 weeks of oral administration, reduce 24 h urine protein levels and decrease creatinine clearance, and attenuate renal fibrosis, indicating that it could attenuate hypertension by protecting against renal damage. Furthermore, we studied the renal protective mechanisms of EGCG, revealing that it could lower malondialdehyde levels, reduce the numbers of infiltrated macrophages and T cells, and induce the apoptosis of NRK-49F cells. Considering that the 67 kD laminin receptor (67LR) binds to EGCG, its role in EGCG-induced fibroblast apoptosis was also investigated. The results showed that an anti-67LR antibody partially abrogated the apoptosis-inducing effects of EGCG on NRK-49F cells. In summary, EGCG may attenuate renal damage and salt-sensitive hypertension via exerting anti-oxidant, anti-inflammatory, and apoptosis-inducing effects on fibroblasts; the last effect is partially mediated by 67LR, suggesting that EGCG represents a potential strategy for treating salt-sensitive hypertension.